Packaging machine



Aug. 19, 1969 H. l. SNYDER PACKAGING momma:

3 Sheets-Sheet 1 Filed Oct. 22, 1965 -7751/6 rzZFT' sk\\\\\sam Illl javwial. 5 7 0122 g3 64 EL JqU/YWM Aug. 19, 1969 H. I. SNYDER 3,461,645

PACKAGING MACHINE Filed Oct. 22, 1965 3 Sheets-Sheet 2 l/ar olcZIfiyciefi 0AM, m, wa 1% Aug. 19, 1969 H. I. SNYDER PACKAGING MACHINE 3 Sheets-Sheet 3 Filed Wt. 22, 1965 Ward? -Zarvldffiydez .-01 M,mam 1/ United States Patent 3,461,645 PACKAGING MACHINE Harold I. Snyder, RR. 3, Dover, Ohio 44622 Filed Oct. 22, 1965, Ser. No. 501,706 Int. Cl. B65b 51/16, 31/00, 61/04 U.S. Cl. 53-112 Claims ABSTRACT OF THE DISCLOSURE The machine comprises mechanism for heat sealing plastic bags with internal pressure. A pair of pressure rolls clamps one end of a plastic bag, containing an article, and previously sealed at its opposite end, a first heat seal is formed responsive to the pressure engagement, the rolls are then rotatably actuated to compress theair within the package, and after a predetermined movement a second heat seal is formed; after which the package b tween the heat seals may be severed.

This invention relates to packaging machines and methods, and concerns particularly packaging machines and methods of the type arranged to enclose an article to be packaged within an hermetically sealed plastic envelope.

It is an object of the invention to provide a machine, and method, of the foregoing type, of improved and simplified character, and which will be more effective and reliable in service.

Among the more specific objects of the invention are to provide a machine, and method, of the foregoing type, wherein the air pressure within the enclosing envelope may be more accurately controlled, wherein a better seal of the envelope is effected, and wherein more uniform operating conditions are insured.

Still further objects of the invention are to provide a machine, and method, of the foregoing type, which are rapid and automatic in operation, and wherein the safety of the operator is insured.

Other objects, advantages and features of the invention will be apparent from the following specification, when taken in connection with the accompanying drawings, wherein a preferred embodiment of the invention is set forth for purposes of illustration.

In the drawings, wherein like reference numerals refer to like parts throughout:

FIG. 1 is a side elevation of a machine, constructed in accordance with and embodying the principles of the present invention, in accordance with one selected embodiment thereof;

FIG. 2 is a detail view of the horizontal actuator, and associated parts;

FIG. 3 is a vertical sectional view of a portion of the machine shown in FIG. 1, taken as indicated by the line 3-3 thereof;

FIG. 4 is a vertical sectional view, taken on the line 4-4 of FIG. 3;

FIG. 5 is a detail view, on an enlarged scale. showing the position of the parts, at the beginning of the operation of the machine;

FIG. 6 is a view similar to FIG. 5, showing the position of the parts in a second step of operation;

FIG. 7 is a view, also similar to FIGS. 5 and 6, showing a still further step in the cycle of operation of the machine;

FIG. 8 is a detail illustrative view, on a further enlarged scale, more particularly showing the sealing operation as conducted in FIG. 6;

FIG. 9 is a view, similar to FIG. 8, but more particularly illustrating the sealing operation as depicted in FIG. 7;

FIG. 10 is a perspective view of the completed package;

FIG. 11 is an electrical diagram; and

ice

FIG. 12 is a hydraulic diagram for the machine.

Referring more particularly to the drawings, and first to FIG. 1 thereof, it Will be seen that: the machine comprises a main base or bed It supported by legs as indicated at 12, 14 and 16.

Upstanding from the central portion of the bed 10 iS a fixed yoke frame composed of a pair of spaced uprights 18 and 20, FIG. 3, connected at their upper ends by a cross member 22, the latter being arranged to support the cylinder 24 of a vertical hydraulic actuator. The vertical hydraulic actuator includes a piston rod 26, FIG. 3, t0 the lower end of which is secured a shiftable actuator yoke composed of a horizontal bar 28 from which depends arms 30 and 32, the latter being slidable respectively within the fixed yoke frame members 18 and 21 As best shown in FIG. 4, it will be seen that the fixed yoke frame member 18 more specifically comprise a pair of spaced apart legs 34 and 36, and the depending arm 30 of the shiftable yoke is box-like in form, and includes opposite side portions as indicated at 38 and 40 slidably engageable, respectively, with the side members 34 and 36. The frame members 34 and 36 are arranged to fixedly support therebetween a pillow block 42 held in place by a set screw 44, which pillow block is arranged rotatably to support one end of a shaft 46 to which is secured the lower compression roll 48, FIG. 3. On the other hand, the depending arm 30 of the shiftable actuator yoke carries at its lower end a pillow block 49 arranged rotatably to support one end of the shaft 50 to which the upper compression roll 52, FIG. 3, is secured. Pillow block 49 is normally held at the lower end of depending arm 30 by the action of a compression spring 54, FIG. 4, the upper end of which engages a bracket 56 which is fixed to the movable arm 30 by means of a screw 58. Associated with the compression spring 54 is a safety switch 60, the function of which will be presently described.

As will be understood, the mechanism particularly shown in FIG. 4, with reference to the yoke frame member 18, is duplicated at the opposite side of the yoke frame, in association with the frame member 20.

It will be seen that by reason of the structure provided, the compression roll 48, FIG. 3, is rotatably supported in fixed position within the yoke frame members 18 and 20, whereas the compression roll 52 is rotatably supported, and is also arranged for vertical movement with the movable yoke arms 30 and 32, under control of the vertical actuator piston 26. Normally roll 52 will be moved downwardly into engagement with roll 48 by means of the vertical actuator piston rod 26, but if the compressive engagement exceeds the strength of compression spring 54, or its companion spring 54a associated with yoke frame member 20, safety switch (or companion safety switch 60a, FIG. 11, associated with frame member 20) will be actuated, for a purpose subsequently to be described, and forming a part of the safety structure of the machine.

Means is provided for rotating the roll 48, in a controlled manner, such means being shown in FIGS. 1, 2 and 3. As shown, this means comprises a pinion 62, FIGS. 2 and 3, secured to shaft 46 and arranged to be operated by a reciprocable rack 64, one end of which is connected to the actuating piston rod 66 of a horizontal actuating cylinder 68, as best shown in FIG. 2. The opposite end of rack 64 is arranged to abut a stop member 70, FIGS. 1 and 2, which stop member limits the rack travel and is positioned within an elongated slot 72 extending longitudinally in the machine bed 10, the stop member being adjustably positioned within the slot and held in place therein by a bolt or screw 74.

Roll 48 has associated therewith a pair of electrodes 76 and 78 which are secured to the roller shaft 46 by collars 80 and 82 respectively. These collars are secured to the shaft 46 by suitable set screws, as will be understood, whereby the angular position of the electrodes on the shaft may be adjusted.

The vertical actuator 24 and the horizontal actuator 68 are preferably hydraulic, powered by means of a motor 84 and pump 86 forming a part of a power pack 88, FIG. 1, comprising a part of the machine. The power pack further includes a second electric motor 90 and an associated fan or blower 92 which is arranged by means of a flexible conduit 94 to direct a suitable jet of air from an exhaust orifice or nozzle 96 toward and into the workpiece or package 98, in the manner as shown in FIG. 5, and as will presently be more specifically described.

The operation of the machine will be best understood by reference to FIGS. to inclusive. The package 98 illustrated in connection with the present machine more particularly comprises an elongated plastic envelope 100, FIG. 10, within which may be disposed an elongated article to be packaged, such for example as a newspaper or calendar, as indicated at 102. In the use of the machine and method of the present invention, the plastic envelope 100 may be presealed at one end, as indicated at 104, FIG. 10, and the article 102 inserted therein. The plastic envelope, with the enclosed article, is then presented to the machine, for the purpose of closing the opposite package end 106. The package, as thus initially presented, is illustrated in FIG. 5, the parts being shown with the air jet nozzle 96 in operation, and just prior to the engagement of the compression roll 52 downwardly into clamping position against the cooperative compression roll 48. In this condition of the parts, and as shown in FIG. 5, the air jet from the nozzle 96 enters the end of the plastic envelope, maintaining the envelope in suitable inflated condition. As will be understood, a strong air blast is not required, but by means of a continuous blast of air, the plastic envelope is maintained extended insuring uniformity in the completed package as will presently appear.

FIGS. 6 and 8 show the parts after the rolls 52 and 48 have been brought into compressing engagement. As best shown in FIG. 8, electrode 78 includes an embedded electric wire 108 by means of which an initial heat seal may be imparted to the end 106 of the plastic envelope.

After such initial heat seal is formed, roll 48 is then advanced counterclockwise by operation of the rack 62 and the horizontal hydraulic actuator 68, to the position shown in FIGS. 7 and 9, so as to bring the electrode 76 info position between the compression rolls, and at the same time compressing the entrapped air within the plastic envelope of the package. As best shown in FIG. 9, electrode 76 includes an embedded wire 110, by means of which a second heat seal may be formed in the end 106 of the plastic envelope. Particular attention is directed to the shaping of the electrode 76, as seen in FIG. 9, and it will be seen that the electrode is formed with an enlargement or compression portion 112 which compresses the envelope to the right of wire 110', as seen in FIG. 9, whereby to firmly hold the superposed laminations of the envelope to be heat sealed, to prevent the undue thinning thereof by the entrapped air pressure in the vicinity of the heat seal formed by the hot wire 110.

As shown in FIG. 7, the machine further preferably comprises a knife 114 pivotally mounted as indicated at 116 on the machine bed, and arranged to be actuated by an electric solenoid 118, the knife being cooperable with a platen 120. In FIG. 7 the initial heat seal formed by the electrode 78 is indicated at 122, and it will be seen that the knife end 114a is adapted to sever the plastic at a position between the two heat seals, after the second heat seal has been formed. In FIG. 10 the second heat seal formed by electrode 76 is indicated at 124,

4 and the severed portion of the plastic envelope is indicated by the reference numeral 126.

The operation of the machine will now be further described by reference to the electric diagram, FIG. 11, and the hydraulic diagram, FIG. 12.

Referring to FIG. 12, hydraulic fluid is supplied to vertical actuator 24 from a four-way valve adapted to be supplied with fluid from pump 86 from fluid reservoir 132. When in normal position valve 130 supplies fluid to the lower end of actuator 24 through pipeline 134, whereby to hold the piston rod 26 in its raised position. The return from actuator 24 leads through pipe 136, and thence through control valve 130 to a return or exhaust line 138. Pipe 136 has an electrical pressure switch 140 disposed therein. Reversal of four-way control valve 130 directs fluid to the upper end of actuator 24 through pipe 136, the return fluid passing through pipe 134 to the exhaust line 138. A solenoid 142 moves valve 130 to the position to direct the inlet fluid to line 134, whereas the solenoid 144 moves the control valve 130 to its opposite position to direct the inlet fluid to line 136.

Similarly the horizontal actuator 68 is arranged to be controlled by a four-way control valve 146 which when in normal position directs inlet fluid from the pump 86 and the supply line 148 to pipe 150 leading to the forward end of horizontal actuator 68 whereby normally to hold rack 62 in its retracted or leftward position as seen in FIG. 12. The return fluid from actuator 68 leads through pipe 152 to return or exhaust line 154 through the control valve 146. Operation of valve 146 reverses the connections to the horizontal hydraulic actuator under control of a solenoid 156 which moves valve 146 to direct fluid to line 150, whereas valve 146 is moved to its opposite position to direct fluid to pipe 152 by operation of solenoid 158. An electrical pressure switch 160- is disposed in line 152. An adjustable restricted orifice valve 162 is disposed in line 148 leading to the horizontal actuator control valve 146. Referring further to FIG. 12, it will be seen that a bypass exhaust line 164 returns to the reservoir from pump 86, in bypass relation, which line includes or has disposed therein an adjustable relief valve 166.

Referring to the electrical circuit diagram, FIG. 11, it will be seen that the normally constantly operable motor 90 for the fan is under control of a switch 168, whereas the motor 84 for the hydraulic pump is under control of a switch 170. Normally these switches are closed and both motors are continuously operable when the machine is in operation.

To impart a cycle of operation to the machine, start switch 172 is actuated so as to energize solenoid 144 to operate four-way control valve 130 to a position to direct hydraulic fluid through pipe 136 to the upper end of the vertical actuator 24, whereby to move the upper roll 52 downwardly into pressure engagement with lower roll 48. When the desired degree of pressure contact has been obtained, in accordance with the adjusted pressure setting of pressure switch 140, solenoid 174, FIG. 11, is energized, so as to sequentially close switches 176 and 178. Solenoid 174 is adjustably controlled, and slow acting, whereby to impart a desired amount of heating to the electrode wire 108, so as to form the first heat seal 122, FIG. 7, for the package.

At the end of the operation of solenoid 174, switch 178 is closed whereby to energize solenoid 158 to thereby operate four-way control valve 146 for the horizontal actuator to a position to direct fluid to the line 152 to thereby move rack 64 forwardly or to the right as seen in FIG. 12, to compress the air within the package, and move the parts to the position shown in FIG. 7.

As adjustable abutment stop 70* is reached, the movement of rack 64 is arrested and pressure builds up within the adjustable pressure switch 160 to thereby energize solenoid 180. Solenoid 180 is also of the adjustable slowacting type, and on operation is arranged to sequentially actuate switches 182, 184 and 186. Operation of switch 182 imparts a desired amount of heating to the electrode 110 whereby to form the second heat seal 124, FIG. 10. Continued operation of solenoid 180 operates switch 184 to energize solenoid 118, FIG. 7, to operate cutter bar 114, and immediately thereafter switch 186 is closed to energize solenoids 142 and 156 to cause simultaneously, the reaction of rack 64 and the raising of the upper pressure roll 52 by the action of the actuators 24 and 68. The cycle of operation is thus complete.

As previously explained, if either safety switch 66 or 60:! is operated, at any time, solenoids 142 and 156 are simultaneously actuated to retract rack 64 and raise the pressure roll 52.

The adjustable orifice 162, FIG. 12, controls the speed of the horizontal actuator 68, and also insures the maintenance of pressure in line 188 leading to the control valve 130, to insure the immediate initial lifting of the pressure roll 152 when valve 130 is properly positioned. Preferably an adjustable orifice control valve 190 is disposed in line 188 for a similar purpose, viz, to maintain pressure in line 143 leading to the control valve 146, and to control the speed of operation of the vertical actuator 24.

As will be understood, the pressure engagement between rolls 52 and 48 may be controlled in its maximum by adjustment of the relief valve 166.

It is obvious that various changes may be made in the specific embodiment of the invention set forth for purposes of illustration without departing from the spirit of the invention. Accordingly, the invention is not to be limited to the specific structure as shown and described, but only as indicated in the following claims.

The invention is hereby claimed as follows:

1. A packaging machine for forming gas-filled pressure sealed packages comprising a pair of cooperative pressure rolls, means to move said rolls transversely toward each other to clamp the open end of an envelope of heat sealable material with the opposed end of said envelope being closed, means for rotating said rolls to advance the envelope therebetween and compress the gas within the cave lope, a heat sealing element means for energizing said element to thereby heat seal the envelope with said gas pressure maintained therein, and clamping means provided between the rolls juxtaposed to the heat sealing element, said clamping means being operable prior to the energizing of the heat sealing element for clamping the heat sealable material to prevent the thinning thereof in the vicinity of the heat seal.

2. A packaging machine for forming gas-filled pressure sealed packages comprising a pair of cooperative pressure rolls, means to move said rolls transversely toward each other to clamp the open end of an envelope of heat sealable material with the opposed end of said envelope being closed, a first heat sealing element for heat sealing the envelope between the pressure rolls, means responsive to the pressure between said rolls for rotating said rolls to advance the envelope therebetween and compress the gas within the envelope, and a second heat sealing element for providing a second heat seal on the envelope in spaced relation to the first heat seal and with the gas pressure maintained therein.

3. A packaging machine as defined in claim 2, wherein cutting means is provided for cutting the envelope between the heat seals.

4. A packaging machine for forming gas-filled pressure sealed packages comprising a pair of cooperative pressure rolls arranged to clamp the open end of an envelope of heat sealable material with the opposed end of said envelope being closed, means responsive to the pressure between said rolls for rotating the rolls to advance the envelope therebetween and compress the gas within the envelope, a heat sealing element, and means responsive to the rotation of the rolls for energizing said element to thereby heat seal the envelope with said gas pressure maintained therein.

5'. A packaging machine for forming gas-filled pressure sealed packages comprising a pair of cooperative pressure rolls arranged to clamp the open end of an envelope of heat sealable material with the opposed end of said envelope being closed, a first heat sealing element, means responsive to the pressure between the rolls for energizing said element to thereby form a first heat seal on the envelope, means operable in timed relation with said energizing means for rotating the rolls to advance the envelope therebetween to compress the gas within the envelope, a second heat sealing element, and means responsive to the rotation of the rolls for energizing said second element to thereby form a second heat seal on the envelope in spaced relation with the first heat seal and with the gas pressure maintained therein.

References Cited UNITED STATES PATENTS 2,737,859 3/1956 Allison et a1.

3,011,295 12/1961 Brugger 53373 X 3,228,167 1/1966 Schmidt 5329 2,877,615 3/1959 Foster 53-112 X TRAVIS C. MCGEHEE, Primary Examiner U.S. Cl. X.R. 53--3'73 

